diff --git a/src/config.h b/src/config.h
index 7850a7e..447fe73 100644
--- a/src/config.h
+++ b/src/config.h
@@ -32,6 +32,6 @@
     /*
     * firmeware version string
     */
-    #define __FIRMWARE__            "2020082101"
+    #define __FIRMWARE__            "2020082103"
 
 #endif // _CONFIG_H
diff --git a/src/hardware/pmu.cpp b/src/hardware/pmu.cpp
index 32b4fe0..bce193e 100644
--- a/src/hardware/pmu.cpp
+++ b/src/hardware/pmu.cpp
@@ -32,14 +32,16 @@ void pmu_setup( TTGOClass *ttgo ) {
     // enable coulumb counter
     if ( ttgo->power->EnableCoulombcounter() ) 
         log_e("enable coulumb counter failed!");    
-    if ( pmu_config.charging_target_voltage <= 4200 ) {
-        if ( ttgo->power->setChargingTargetVoltage( AXP202_TARGET_VOL_4_2V ) )
-            log_e("target voltage 4.2V set failed!");
-    }
-    else {
+    if ( pmu_config.high_charging_target_voltage ) {
+        log_i("set target voltage to 4.36V");
         if ( ttgo->power->setChargingTargetVoltage( AXP202_TARGET_VOL_4_36V ) )
             log_e("target voltage 4.36V set failed!");
     }
+    else {
+        log_i("set target voltage to 4.2V");
+        if ( ttgo->power->setChargingTargetVoltage( AXP202_TARGET_VOL_4_2V ) )
+            log_e("target voltage 4.2V set failed!");
+    }
     if ( ttgo->power->setChargeControlCur( 300 ) )
         log_e("charge current set failed!");
     if ( ttgo->power->setAdcSamplingRate( AXP_ADC_SAMPLING_RATE_200HZ ) )
@@ -137,7 +139,7 @@ void pmu_save_config( void ) {
         doc["silence_wakeup_time_vbplug"] = pmu_config.silence_wakeup_time_vbplug;
         doc["experimental_power_save"] = pmu_config.experimental_power_save;
         doc["compute_percent"] = pmu_config.compute_percent;
-        doc["charging_target_voltage"] = pmu_config.charging_target_voltage;
+        doc["high_charging_target_voltage"] = pmu_config.high_charging_target_voltage;
         doc["designed_battery_cap"] = pmu_config.designed_battery_cap;
 
         if ( serializeJsonPretty( doc, file ) == 0) {
@@ -166,13 +168,13 @@ void pmu_read_config( void ) {
                 log_e("update check deserializeJson() failed: %s", error.c_str() );
             }
             else {
-                pmu_config.silence_wakeup = doc["silence_wakeup"].as<bool>() | false;
-                pmu_config.silence_wakeup_time = doc["compute_percent"].as<int8_t>() | 60;
-                pmu_config.silence_wakeup_time_vbplug = doc["compute_percent"].as<int8_t>() | 3;
-                pmu_config.experimental_power_save = doc["experimental_power_save"].as<bool>() | false;
-                pmu_config.compute_percent = doc["compute_percent"].as<bool>() | false;
-                pmu_config.charging_target_voltage = doc["charging_target_voltage"].as<int32_t>() | 4200;
-                pmu_config.designed_battery_cap = doc["designed_battery_cap"].as<int32_t>() | 300;
+                pmu_config.silence_wakeup = doc["silence_wakeup"] | false;
+                pmu_config.silence_wakeup_time = doc["compute_percent"] | 60;
+                pmu_config.silence_wakeup_time_vbplug = doc["compute_percent"] | 3;
+                pmu_config.experimental_power_save = doc["experimental_power_save"] | false;
+                pmu_config.compute_percent = doc["compute_percent"] | false;
+                pmu_config.high_charging_target_voltage = doc["high_charging_target_voltage"] | false;
+                pmu_config.designed_battery_cap = doc["designed_battery_cap"] | 300;
             }        
             doc.clear();
         }
diff --git a/src/hardware/pmu.h b/src/hardware/pmu.h
index 422e026..279580e 100644
--- a/src/hardware/pmu.h
+++ b/src/hardware/pmu.h
@@ -30,13 +30,13 @@
     #define PMU_JSON_CONFIG_FILE    "/pmu.json"
 
     typedef struct {
+        int32_t designed_battery_cap = 300;
+        int32_t silence_wakeup_time = 60;
+        int32_t silence_wakeup_time_vbplug = 3;
+        bool high_charging_target_voltage = true;
         bool compute_percent = false;
         bool experimental_power_save = false;
         bool silence_wakeup = true;
-        uint8_t silence_wakeup_time = 60;
-        uint8_t silence_wakeup_time_vbplug = 3;
-        int32_t charging_target_voltage = 3200;
-        int32_t designed_battery_cap = 300;
     } pmu_config_t;
 
     /*
diff --git a/ttgo-t-watch2020_v1.ino.bin b/ttgo-t-watch2020_v1.ino.bin
index c7f7827..abe4fbb 100644
Binary files a/ttgo-t-watch2020_v1.ino.bin and b/ttgo-t-watch2020_v1.ino.bin differ
diff --git a/ttgo-t-watch2020_v1.version.json b/ttgo-t-watch2020_v1.version.json
index 9468d45..bed779b 100644
--- a/ttgo-t-watch2020_v1.version.json
+++ b/ttgo-t-watch2020_v1.version.json
@@ -1 +1 @@
-{"version":"2020082101","host":"http://www.neo-guerillaz.de","file":"ttgo-t-watch2020_v1.ino.bin"}
+{"version":"2020082103","host":"http://www.neo-guerillaz.de","file":"ttgo-t-watch2020_v1.ino.bin"}